Effects of Mn and Cr Additions on the Recrystallization Behavior of Al-Mg-Si-Cu Alloys

Upsetting tests on two newly developed Mn and Cr-containing Al-Mg-Si-Cu alloys with various Mn contents were carried out at a speed of 15 mm/s under upsetting temperature of 450 °C after casting and subsequent homogenization heat treatment using a 300-Tone hydraulic press. STEM experiments revealed that Mn and Cr-containing α-Al (MnCrFe)Si dispersoids formed during homogenization showed a strong pinning effect on dislocations and grain boundaries, which could effectively inhibit recovery and recrystallization during hot deformation in the two alloys. Recrystallization fractions after solution heat treatment following hot deformation were measured by EBSD technique. It was found that the recrystallization fractions of the two alloys were less than 30%, giving rise to lower recrystallization fraction in the alloy with higher amount of Mn, which had higher number density of dispersoids. This implied that the finely distributed α-dispersoids were rather stable against coarsening and they stabilized the microstructure by inhibiting dislocation recovery and recrystallization during elevated temperature exposure. Increasing the content of Mn could increase the number density as well as the aspect ratio of the dispersoids, and more significantly, the effect of retardation on recrystallization were further enhanced.

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Static Recrystallization in Aluminum/Graphene Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.1636 ◽

2021 ◽

Vol 1016 ◽

pp. 1636-1641

Author(s):

Xiao Dong Wu ◽

Xiao Li Liu ◽

Ling Fei Cao ◽

Guang Jie Huang

Keyword(s):

Annealing Temperature ◽

Static Recrystallization ◽

Recrystallization Behavior ◽

High Annealing Temperature ◽

Graphene Composite ◽

Pinning Effect ◽

High Annealing ◽

Rolled Aluminum ◽

Strong Pinning ◽

Cold Rolled

The aim of this work was to analyze the recrystallization behavior of cold rolled Aluminum/graphene composites during annealing. The Aluminum/graphene composite was cold rolled firstly, and then annealed at different temperature (250°C, 300°C, 350°C, 400°C) and for various time (1 h, 2 h, 8 h, 32 h). Full recrystallization did not occur until the annealing temperature was above 300 °C. With annealing temperature increasing from 250 to 300°C, the hardness of the composites decreased from 49.6 to 27.6 HV. Grain growth were not observed at high annealing temperature and longer annealing time, which suggested that Graphene has strong pinning effect on the grain boundary of Aluminum.

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Development of Al-Fe-(Cu) Series Alloys for Aluminum Cables and the Related Annealing Behaviors

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.937 ◽

2018 ◽

Vol 941 ◽

pp. 937-942

Author(s):

Hua Chen ◽

Rong Kai Yang ◽

Xiao Dong Wu ◽

Yuan Yuan ◽

Bing Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Heat Treatment ◽

Electrical Conductivity ◽

Electron Backscattered Diffraction ◽

Cu Alloy ◽

Cu Alloys ◽

Backscattered Electron ◽

Ebsd Technique ◽

Scanning Electron

In this work, Al-Fe-(Cu) alloys for aluminum cables were designed and the related annealing behaviors were discussed in detail to help understand the influence of processing and heat treatment on the electrical conductivity and mechanical properties of the studied alloys. The interaction between different solute elements was tracked by using hardness and electrical conductivity testing. The microstructure was investigated by using Electron Backscattered Diffraction (EBSD) technique, along with Scanning Electron Microscopy with Backscattered Electron Detector (BSE). The results show that the conductivities of Al-Fe-Cu alloy increased with the elongated annealing time, and reaches its maximum at 6 h, when annealed at temperatures from 275 °C to 375 °C. The addition of Fe to Al can strengthen the alloy and decrease its conductivity slightly, while the addition of Cu will influence the alloy conductivity significantly. The morphologies of precipitates will change with different amount of alloying elements as well.

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Precipitation Strengthening in Ni–Cu Alloys Fabricated Using Wire Arc Additive Manufacturing Technology

Metals ◽

10.3390/met9010105 ◽

2019 ◽

Vol 9 (1) ◽

pp. 105 ◽

Cited By ~ 3

Author(s):

Olexandra Marenych ◽

Andrii Kostryzhev ◽

Chen Shen ◽

Zengxi Pan ◽

Huijun Li ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Wear Resistance ◽

Room Temperature ◽

Air Cooling ◽

Number Density ◽

Slow Cooling ◽

Additive Manufacturing Technology ◽

Cu Alloys ◽

Wire Arc Additive Manufacturing

Two Ni–Cu alloys, Monel K500 and FM60, with various contents of Ti, Mn, Al, Fe and C were deposited in the form of plates on a metal base plate using wire arc additive manufacturing technology. Three deposition speeds have been applied: 300, 400 and 500 mm/min. To modify the as-welded microstructure and properties, the deposited walls/plates have been subjected to two heat treatment procedures: annealing at 1100 °C for 15 min, slow cooling to 610 °C, ageing at this temperature for 8 h and either (i) air cooling to room temperature or (ii) slow cooling to 480 °C, ageing at this temperature for 8 h and air cooling to room temperature. The microstructure characterisation and mechanical properties testing have been conducted for each of the 18 chemistry/processing conditions. The dependences of the precipitate’s parameters (size, number density and chemistry), mechanical properties and wear resistance on the alloy composition, deposition speed and heat treatment have been obtained. In Monel K500, the precipitates were mainly of the TiC/TiCN type, and in FM60, they were of the MnS and TiAlMgO types. Monel K500 has shown higher hardness, strength, toughness and wear resistance in all studied conditions. Ageing at 610 °C improved properties in both alloys following the precipitation of new particles. Ageing at 480 °C could result in a properties loss if the particle coarsening (decrease in number density) took place.

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Dynamic recrystallization behavior during hot deformation of as-cast 4Cr5MoSiV1 steel

Journal of Materials Science ◽

10.1007/s10853-021-05792-7 ◽

2021 ◽

Vol 56 (14) ◽

pp. 8762-8777

Author(s):

Yahui Han ◽

Changsheng Li ◽

Jinyi Ren ◽

Chunlin Qiu ◽

Shuaishuai Chen ◽

...

Keyword(s):

Dynamic Recrystallization ◽

Hot Deformation ◽

Recrystallization Behavior ◽

Dynamic Recrystallization Behavior

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Dynamic Recrystallization Behavior of Medium Carbon Cr-Ni-Mo-Nb Steel During Hot Deformation

Journal of Iron and Steel Research International ◽

10.1016/s1006-706x(15)60040-1 ◽

2015 ◽

Vol 22 (3) ◽

pp. 264-271 ◽

Cited By ~ 16

Author(s):

Shi-li Zhu ◽

Hua-zhen Cao ◽

Jian-song Ye ◽

Wen-hao Hu ◽

Guo-qu Zheng

Keyword(s):

Dynamic Recrystallization ◽

Hot Deformation ◽

Recrystallization Behavior ◽

Medium Carbon ◽

Dynamic Recrystallization Behavior

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On the Use of EBSD and Microhardness to Study the Microstructure Properties of Tungsten Samples Prepared by Selective Laser Melting

Materials ◽

10.3390/ma14051215 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1215

Author(s):

Mirza Atif Abbas ◽

Yan Anru ◽

Zhi Yong Wang

Keyword(s):

Selective Laser Melting ◽

Electron Backscatter Diffraction ◽

Fusion Reactors ◽

Laser Melting ◽

Kikuchi Pattern ◽

Plasma Facing Components ◽

Electron Backscatter ◽

Ebsd Technique ◽

Temperature Exposure ◽

Backscatter Diffraction

Additively manufactured tungsten and its alloys have been widely used for plasma facing components (PFCs) in future nuclear fusion reactors. Under the fusion process, PFCs experience a high-temperature exposure, which will ultimately affect the microstructural features, keeping in mind the importance of microstructures. In this study, microhardness and electron backscatter diffraction (EBSD) techniques were used to study the specimens. Vickers hardness method was used to study tungsten under different parameters. EBSD technique was used to study the microstructure and Kikuchi pattern of samples under different orientations. We mainly focused on selective laser melting (SLM) parameters and the effects of these parameters on the results of different techniques used to study the behavior of samples.

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